Golf clubhead to shaft coupling system

ABSTRACT

A golf clubhead to shaft coupling system which includes a flexure joint providing for relative movement between the golf clubhead and the shaft. The flexure joint may be machined into the hosel of the golf club, or may be in a separate coupling piece that couples the golf clubhead to the hosel. In one aspect of the invention, a helical coil is machined into the coupling to provide some relative movement between the clubhead and the shaft for increased golfer “feel” during the golf stroke.

CROSS REFERENCE TO RELATED APPLICATION

[0001] This application is not related to any other application.

TECHNICAL FIELD

[0002] This invention relates to a golf clubhead to shaft coupling system, and more particularly to such a system which includes a flexure joint providing for relative movement between the golf clubhead and the shaft.

BACKGROUND OF THE INVENTION

[0003] In golf, there has been much effort and design toward creating the optimum flex and flex points in the shaft of the golf club, especially for the swinging clubs. There has also been a continual striving in the industry to increase the feel and a desire to cause the ball to stay on the club face longer to increase control and in some cases increase spin. This may also contribute to the feel on putter-type clubs and others.

[0004] There have been multiple attempts to achieve these objectives, such as by softening the metal or the surface out of which the clubhead is constructed. While this may have advantages in some ways, it has disadvantages due to the softness of the club and the wear factors.

[0005] It is an object of this invention to provide an additional flex point at or near the hosel of the golf club, or in cases in which there is no hosel, near where the shaft is coupled to the clubhead.

[0006] There has also been an increasing desire to fit, design or configure a golf club, its head or its shaft flex, to the particular swing of a golf, and to include a variance of that flex depending on the club being hit. It is also an object of this invention to provide golf club coupling system that varies the flex in the coupling flexure portion to a particular golfer's swing or swing speed, and to the particular clubs in the bag that the particular golfer is hitting.

BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Preferred embodiments of the invention are described below with reference to the following accompanying drawings.

[0008]FIG. 1 is a front elevation view of a golf club with an embodiment of the golf clubhead to shaft coupling system contained in the hosel thereof;

[0009]FIG. 2 is a front elevation partial section view of one embodiment of a coupling system contemplated by this invention on a putter;

[0010]FIG. 3 is section 3-3 from FIG. 2;

[0011]FIG. 4 is an elevation view of an embodiment of a coupling system contemplated by this invention, on the hosel of a golf iron;

[0012]FIG. 5 is a side elevation view of a golf iron with an embodiment of a coupling system contemplated by this invention on the hosel thereof, showing the striking of a golf ball and the flexing of the coupling system;

[0013]FIG. 6 is another embodiment of a flexure portion of a coupling system which may be utilized in this invention, showing a honeycomb configuration in the metal to allow the desired flex;

[0014]FIG. 7 is a front elevation view of another embodiment of a coupling system contemplated by this invention, wherein the coupling system is a separate piece which is between the clubhead and the golf shaft; and

[0015]FIG. 8 is a front elevation view of another embodiment of a coupling system contemplated by this invention, only wherein the flexure portion includes one or more slits cut into the hosel (or coupling) on one or more sides.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Many of the fastening, connection, manufacturing and other means and components utilized in this invention are widely known and used in the field of the invention described, and their exact nature or type is not necessary for an understanding and use of the invention by a person skilled in the art or science; therefore, they will not be discussed in significant detail. Furthermore, the various components shown or described herein for any specific application of this invention can be varied or altered as anticipated by this invention and the practice of a specific application or embodiment of any element may already be widely known or used in the art or by persons skilled in the art or science; therefore, each will not be discussed in significant detail.

[0017] The terms “a”, “an”, and “the” as used in the claims herein are used in conformance with long-standing claim drafting practice and not in a limiting way. Unless specifically set forth herein, the terms “a”, “an”, and “the” are not limited to one of such elements, but instead mean “at least one”.

[0018]FIG. 1 is a front elevation view of a golf club with an embodiment of a coupling system contemplated by this invention contained within the hosel, showing golf club 100, golf club grip 101, golf club shaft 102, golf clubhead 103 with club face 104 and hosel 105. In the flexure portion 106 of the hosel 105, there are helical grooves cut into the metal hosel and which provide flex, as shown more fully below in other figures.

[0019]FIG. 2 is a front elevation partial section view of an embodiment contemplated by this invention, showing golf club shaft 102, hosel 105, club face 104 on clubhead 103. The flexure portion 106 of hosel 105 is shown in cross sectional view and which provides the flexure contemplated by this invention. It will be noted by those of ordinary skill in the art that there may be a desire to limit the magnitude of the flexure portion so that too much flexure is not incurred during a swing, whether it is a putter or whether it is an iron club or what is generally referred to as a “wood” (although many woods today are made of metal and other materials).

[0020] In order to provide a limit to the flexure in those aspects of the invention where a limit is desired, the limiter 128 is shown attached to shaft 102 within limiter guide 124. Key 126 and elastomer rings 121 and bottom surface 123 of limiter section 122 are shown within clubhead 103, with plug 125 being located toward the sole 103 a of the clubhead. Internal hosel section 120 may, but need not, be one piece with hosel 105 and contribute to the limiting function.

[0021] As the club face 104 makes contact with, or impacts a golf ball, forces are exerted which will cause flexure of the coupling system, in this case the flexure portion 106 of hosel 105. This will occur to a more limited degree with a putter than an iron or a wood, and will vary with the nature of the swing and the impact. Limiter 128 will then control or limit the amount of flexure of the clubhead 103 relative to the shaft 102, as shown.

[0022]FIG. 3 is section 3-3 from FIG. 2 and illustrates shaft 102, clubhead 103, plug 125, elastomer ring 121, bottom surface 122 of limiter part 122 and limiter 128. Hosel 105 with flexure portion 106 is also shown with arrows 129 indicating a flexure of the shaft 102 relative to clubhead 103.

[0023]FIG. 4 is a front elevation view of a golf club iron which includes an embodiment of a coupling system contemplated by this invention. FIG. 4 shows clubhead 140 with striking surface 142 containing grooves 141 across the striking face 142. The sole 140 a of clubhead 140 is also shown. Golf club shaft 102 is shown attached to hosel 138 and flexure portion 139 of hosel 138 is also shown.

[0024] It will be appreciated by those of ordinary skill in the art that depending upon the club being swung, as well as the expected forces imposed on the flexure portion 139 of the hosel 138, there may or may not be a need or desire for a limiter within the hosel. Instead, the stiffness and the cutting of the helical groove, if that is what is used, may inherently provide the desired limiting function.

[0025]FIG. 5 is a side elevation view of a golf club iron with an embodiment of a coupling system contemplated by this invention, showing clubhead 140, hitting surface 142, rear side 145, hosel 138 and a golf ball 144 being struck by clubhead 140. FIG. 5 illustrates flexure in the flexure portion of the hosel 138 at impact, which would likely cause the golf ball 144 to stay on the club face 142 longer than it otherwise would without the additional flexure provided by the coupling system of this invention. Additionally, depending upon the nature of the shot and the flexure portion of the hosel or of the coupling system, the rebounding of the flexure or the response of the metal in the flexure portion will cause the striking surface 142 to accelerate through the ball as it is struck and potentially cause more spin on the ball as it leaves the club face.

[0026]FIG. 6 is a view of another embodiment of a flexure portion 163 which may be utilized in a coupling system contemplated by this invention. FIG. 6 illustrates a coupling system 160 with a flexure portion 163 attached to first section 161 and second section 162. First section 161 would preferably be configured to attach to or couple with a golf shaft (either as part of a hosel or a separate coupling member) and second section 162 would either be part of a hosel or a part of a coupler which would attach to a clubhead.

[0027] The flexure portion 163 includes ridge members 164 and apertures 165, the apertures 165 being configured with ridges 164 to provide the desired amount of flexure at the flexure portion 163.

[0028]FIG. 7 is a front elevation view of another embodiment of this invention, showing a coupling system 170, golf shaft 171, clubhead 172, flexure portion 176 with cut helical grooves 177, coupling member 175 which is configured with an aperture 179 to receive and attach to shaft 171. The second side of coupler 175 includes a male portion 178 which inserts into a hosel or a clubhead for attachment of the coupler 175 to a hosel or a clubhead in normal fashion or in any other fashion.

[0029] An embodiment of the invention where helical coils are used, the helical coils may be precisely cut to the desired flexure, tension and compression necessary to allow the coupling system or coupler to provide the desired forces for the golf club application. It is also evident that the flexure portion of the hosel or coupling, has a flexure different than that of the remainder of the hosel or coupling, preferably a greater flexure.

[0030] In embodiments of the invention to be applied to golf club putters, the helical groove. portion may provide up to approximately fifty one-thousandths of an inch of movement side-to-side (translational or transverse) to allow for flexure of the hosel or coupler. The helical coils may be machined into the flexure portion in any one of a number of ways, such as by Helical Products, Inc., a corporation existing in the United States. Although the preferred material out of which the spring and/or coupler (flexure portion and/or coupler) or hosel is constructed is stainless steel metal, no one material is required to practice the invention.

[0031]FIG. 8 is a front elevation view of another embodiment of a coupling system contemplated by this invention, only wherein the flexure portion includes one or more slits cut into the hosel (or coupling) on one or more sides. FIG. 8 shows clubhead 190 with striking face 193, sole 190 a, scoring lines 191 and hosel 194. While three slots 195 are imparted in hosel 194 in the embodiment shown, there may be one or more slots 195 created for a given application. In this embodiment, there may be one or more similar slots in on the opposite side of the hosel 194 to absorb some of the flexure generated by the swinging of the club. The slots may also be used in the separate coupling embodiment, for any type of club, namely putters, irons or woods.

[0032] There has also been an increasing desire to fit, design or configure a golf club, its head or its shaft flex, to the particular swing of a golf, and to include a variance of that flex depending on the club being hit, which embodiments of this invention provide the opportunity to accomplish. For instance aspects of this invention provide a golf club set coupling system that provides a varied flex in the clubhead to shaft coupling which adjusts the amount of flexure to a particular golfer's swing or swing speed, and to the particular clubs in the bag, or both. For instance, the desired amount of flexure for a given golfer may be decided to include more flex for a pitching wedge than for a three iron, or visa versa. By way of further example, the flexure can be increasing or decreasing progressively through a clubset, either via a stiffer flexure or a decreasing flexure from club to club in a set. A set may be any three or more correlated or matched clubs, and they need not be sequential (for instance the progression may be from the pitching wedge to the six iron to the three iron (either increasing or decreasing flexure). The depth, width or circumferential distance cut may be varied depending on the application and the desired hitting characteristics. The lateral flexure figures are known to those of ordinary skill in the art, and the pre-determined flexures may be readily ascertained from such information.

[0033] As will be appreciated by those of reasonable skill in the art, there are numerous embodiments to this invention, and variations of elements and components which may be used, all within the scope of this invention.

[0034] One embodiment of this invention, for example, is a golf clubhead comprised of: a clubface, a sole and a hosel; wherein the hosel includes a first end attached to the clubhead and a second end configured for attachment to a golf club shaft, and the hosel further including a flexure portion between the first end and the second end, the flexure portion having a pre-determined lateral flexibility in response to forces imparted on the clubhead. The clubhead may be for a putter, iron or wood. In one aspect of the invention, the flexure portion of the hosel is defined by helical spring coils having a predetermined lateral flexure in response to lateral forces. In another aspect of the invention, the pre-determined lateral flexibility is determined such that it is responsive to forces imparted on the clubhead during the striking of a golf ball, whereas in other aspects the pre-determined lateral flexibility is determined such that it is responsive to forces imparted on the flexure portion during the swinging of the clubhead.

[0035] In further or other embodiments, the flexure portion of the hosel (or the coupling as set forth below) is defined by at least one slot imparted in a first side of the hosel, the at least one slot having a predetermined lateral flexure which flexes in response to lateral forces. In a further embodiment of the foreging, the flexure portion of the hosel is further defined by at least one slot imparted in a second side of the hosel, the at least one slot having a predetermined lateral flexure which flexes in response to lateral forces.

[0036] In another embodiment, a golf club is provided which is comprised of: a shaft with a first end and a second end, the first end having a grip thereon and the second end being attached to a golf clubhead; the golf clubhead comprising: a clubface, a sole and a hosel; wherein the hosel includes a first end attached to the clubhead and a second end configured for attachment to a golf club shaft, and the hosel further including a flexure portion between the first end and the second end, the flexure portion having a pre-determined lateral flexibility in response to forces imparted on the clubhead. In this embodiment, the pre-determined lateral flexibility is determined such that it is responsive to forces imparted on the clubhead while the golf club is being swung.

[0037] In another embodiment of the invention, a golf clubhead-to-shaft coupling is provided, which comprises: a first end configured for attachment to golf shaft; a second end configured for attachment to a golf clubhead; a flex portion between the first end and the second end, the flex portion including a pre-determined lateral flexibility related to forces imparted on the golf clubhead. In a further embodiment of the coupling, the flexure portion is defined by helical spring coils having a predetermined lateral flexure in response to lateral forces.

[0038] In an alternative further embodiment, the flexure portion is defined by at least one slot imparted in a first side of the coupling, the at least one slot having a predetermined lateral flexure which flexes in response to lateral forces. In a yet further embodiment of the slot coupling, the flexure portion is further defined by at least one slot imparted in a second side of the coupling, the at least one slot having a predetermined lateral flexure which flexes in response to lateral forces.

[0039] In another embodiment, a golf club set is provided, the set including a flexure portion of either a hosel or a coupling, and the flexure portion: progressively increases from a lower numbered iron to a higher numbered iron; or alternatively progressively increases from a higher numbered iron to a lower numbered iron, i.e. a different flexure in one club in a correlated or matched set relative to another club in the same matched or correlated set.

[0040] In yet another aspect of the invention, which may also be combined with prior aspects, the specific flexure may be matched or correlated to the swing or desires of the golfer.

[0041] In a golf club set embodiment utilizing the invention, a set of matched golf clubheads may be provided which comprises: a first clubhead with a hosel which includes a flexure portion with a first magnitude of flexure; a second clubhead with a hosel which includes a flexure portion with a second magnitude of flexure; and a third clubhead with a hosel which includes a flexure portion with a third magnitude of flexure.

[0042] Further embodiments of the set may be further: wherein the first magnitude of flexure, the second magnitude of flexure and the third magnitude of flexure, are approximately equal; and/or wherein the first magnitude of flexure, the second magnitude of flexure and the third magnitude of flexure progressively increase.

[0043] In another aspect of the golf set embodiments, a set of matched golf clubs may be provided which are comprised of: a first club with a first clubhead to shaft coupler which includes a flexure portion with a first magnitude of flexure; a second club with a second clubhead to shaft copuler which includes a flexure portion with a second magnitude of flexure; and a third club with a third clubhead to shaft coupler which includes a flexure portion with a third magnitude of flexure. Further embodiments of this may be wherein the first magnitude of flexure, the second magnitude of flexure and the third magnitude of flexure, are approximately equal; and/or wherein the first magnitude of flexure, the second magnitude of flexure and the third magnitude of flexure progressively increase.

[0044] In compliance with the statute, the invention has been described in language more or less specific as to structural and methodical features. It is to be understood, however, that the invention is not limited to the specific features shown and described, since the means herein disclosed comprise preferred forms of putting the invention into effect. The invention is, therefore, claimed in any of its forms or modifications within the proper scope of the appended claims appropriately interpreted in accordance with the doctrine of equivalents. 

I/We claim:
 1. A golf clubhead comprised of: a clubface, a sole and a hosel; wherein the hosel includes a first end attached to the clubhead and a second end configured for attachment to a golf club shaft, and the hosel further including a flexure portion between the first end and the second end, the flexure portion having a pre-determined lateral flexibility in response to forces imparted on the clubhead.
 2. A golf clubhead as recited in claim 1, and further wherein the golf club is a putter.
 3. A golf clubhead as recited in claim 1, and further wherein the golf club is an iron.
 4. A golf clubhead as recited in claim 1, and further wherein the flexure portion of the hosel is defined by helical spring coils having a predetermined lateral flexure in response to lateral forces.
 5. A golf clubhead as recited in claim 1, and further wherein the pre-determined lateral flexibility is responsive to forces imparted on the clubhead during the striking of a golf ball.
 6. A golf clubhead as recited in claim 1, and further wherein the pre-determined lateral flexibility is responsive to forces imparted on the clubhead while in motion.
 7. A golf clubhead as recited in claim 1, and further wherein the flexure portion of the hosel is defined by at least one slot imparted in a first side of the hosel, the at least one slot having a predetermined lateral flexure which flexes in response to lateral forces.
 8. A golf clubhead as recited in claim 7, and further wherein the flexure portion of the hosel is further defined by at least one slot imparted in a second side of the hosel, the at least one slot having a predetermined lateral flexure which flexes in response to lateral forces.
 9. A golf club comprised of: a shaft with a first end and a second end, the first end having a grip thereon and the second end being attached to a golf clubhead; the golf clubhead comprising: a clubface, a sole and a hosel; wherein the hosel includes a first end attached to the clubhead and a second end configured for attachment to a golf club shaft, and the hosel further including a flexure portion between the first end and the second end, the flexure portion having a pre-determined lateral flexibility in response to forces imparted on the clubhead.
 10. A golf club as recited in claim 9, and further wherein the pre-determined lateral flexibility is responsive to forces imparted on the clubhead while the golf club is being swung.
 11. A golf clubhead-to-shaft coupling comprising: a first end configured for attachment to golf shaft; a second end configured for attachment to a golf clubhead; a flex portion between the first end and the second end, the flex portion including a pre-determined lateral flexibility related to forces imparted on the golf clubhead.
 12. A golf clubhead-to-shaft coupling as recited in claim 11, and further wherein the flexure portion is defined by helical spring coils having a predetermined lateral flexure in response to lateral forces.
 13. A golf clubhead-to-shaft coupling as recited in claim 11, and further wherein the flexure portion is defined by at least one slot imparted in a first side of the coupling, the at least one slot having a predetermined lateral flexure which flexes in response to lateral forces.
 14. A golf clubhead-to-shaft coupling as recited in claim 13, and further wherein the flexure portion is further defined by at least one slot imparted in a second side of the coupling, the at least one slot having a predetermined lateral flexure which flexes in response to lateral forces.
 15. A set of matched golf clubheads, comprising: a first clubhead with a hosel which includes a flexure portion with a first magnitude of flexure; a second clubhead with a hosel which includes a flexure portion with a second magnitude of flexure; and a third clubhead with a hosel which includes a flexure portion with a third magnitude of flexure.
 16. A set of matched golf clubheads as recited in claim 15, and further wherein the first magnitude of flexure, the second magnitude of flexure and the third magnitude of flexure, are approximately equal.
 17. A set of matched golf clubheads as recited in claim 15, and further wherein the first magnitude of flexure, the second magnitude of flexure and the third magnitude of flexure progressively increase.
 18. A set of matched golf clubs, comprising: a first club with a first clubhead to shaft coupler which includes a flexure portion with a first magnitude of flexure; a second club with a second clubhead to shaft copuler which includes a flexure portion with a second magnitude of flexure; and a third club with a third clubhead to shaft coupler which includes a flexure portion with a third magnitude of flexure.
 19. A set of matched golf clubs as recited in claim 18, and further wherein the first magnitude of flexure, the second magnitude of flexure and the third magnitude of flexure, are approximately equal.
 20. A set of matched golf clubheads as recited in claim 18, and further wherein the first magnitude of flexure, the second magnitude of flexure and the third magnitude of flexure progressively increase. 